In general, electronic devices, such as a portable terminal, a portable multimedia player (PMP), and an MPEG-1 audio layer-3 (MP3), refer to devices with which users may use various types of content while carrying them. Users mostly use portable electronic devices while moving thanks to easy portability and various functions loaded therein. The portable electronic devices have various form factors according to applications, the trends of the times, or consumers' requirements, and in recent years, bar-type electronic devices (such as a smart phone, a tablet PC, and the like) having a variety of functions have been widely used.
These portable terminals have various types of keys installed on the front, rear, and side surfaces thereof. The portable terminals may have home keys using fingerprint recognition sensors in order to enhance security and usability.